#include<stdio.h>
#include<string.h>
int main()
{
    char str[50];
    scanf("%c",&str[50]);
    if(red)
    {
        printf("Stop");
    }
    else
    if(yellow)
    {
        printf("Ready");
    }
    else
    if(green)
    {
        printf("Go");
    }
    else
    {
        printf("Invalid input");
    }
    return 0;
    
}